This undated image made available by Teva Women's Health shows the packaging for their Plan B One-Step (levonorgestrel) tablet, one of the brands known as the "morning-after pill."

U.S. regulators on Tuesday lowered the age limit for Plan B One-Step emergency contraception, approving it for sale to girls as young as 15 and agreeing it will be available without a prescription and on store shelves instead of behind pharmacy counters, Food and Drug Administration officials announced.

The move, which grants an amended application by drugmaker Teva Women's Health Inc., is a separate action from a federal judge's ruling earlier this month that ordered the FDA to make the so-called "morning after pill" available to girls and women of all reproductive ages. It comes just days before U.S. District Court Judge Edward Korman's decision is set to take effect.

"The FDA’s approval of Teva’s current application for Plan B One-Step is independent of that litigation and this decision is not intended to address the judge’s ruling," agency officials said in a statement.

Under the FDA's latest action, the emergency contraception will now be labeled as not for sale to those younger than 15 and will require proof of age. It will not be available where age cannot be verified, but will be sold during normal retail hours outside pharmacy hours, likely in the women's health or family planning aisles. In addition, Teva has arranged to have a security tag placed on all cartons to prevent theft.

The action alters the FDA’s controversial decision in December 2011 not to make Plan B One-Step available over the counter to girls younger than 17. At that time, Health and Human Services Secretary Kathleen Sebelius overruled an FDA committee recommendation -- and Commissioner Margaret Hamburg -- to force the agency to limit access to emergency contraception to younger girls. That move was hotly disputed by medical experts who said the drug was safe and effective for girls and women and widely regarded as an effort to avoid political fallout for President Barack Obama's administration during an election year.

In granting Teva’s amended application Tuesday, Hamburg said it was based on science that shows access to emergency contraception has the potential to decrease the rate of unintended pregnancies in the U.S.

“The data reviewed by the agency demonstrated that women 15 years of age and older were able to understand how Plan B One-Step works, how to use it properly, and that it does not prevent the transmission of a sexually transmitted disease,” Hamburg said in a statement.

U.S. Department of Justice officials are still considering whether to appeal Korman's April 5 decision, which reversed the 2011 FDA ruling and orders the agency to make emergency contraception products that contain levonorgestrel available without age or so-called “point of sale” restrictions. The FDA has 30 days, or until May 5 or 6 to take action.

In a sharply worded 59-page ruling, Korman said the FDA's decisions about the drug were "politically motivated, scientifically unjustified and contrary to agency precedent."

The ruling appeared to apply to Plan B One-Step and generic brands of the morning-after pill, although Korman gave the FDA the option of limiting the expanded access just to Plan B One-Step, if the agency believed that the one-pill option was better than products that use two pills.

"While there are still practical questions to resolve, this is an important step forward to expand access to emergency contraception and for preventing unintended pregnancy," agency President Cecile Richards said in a statement. "Emergency contraception is a safe and effective form of birth control that can prevent pregnancy if taken within five days of unprotected sex. This decision will eliminate some of the biggest barriers and hurdles that women face in getting emergency contraception when they need it, which means many more women will be able to prevent unintended pregnancy."

However, the move to approve Teva's application without addressing the judge's order was sharply criticized by the reproductive rights advocates who brought the lawsuit in 2001.

“Lowering the age restriction to 15 for over-the-counter access to Plan B One-Step may reduce delays for some young women -- but it does nothing to address the significant barriers that far too many women of all ages will still find if they arrive at the drugstore without identification or after the pharmacy gates have been closed for the night or weekend," said Nancy Northup, president and chief executive of the Center for Reproductive Rights, which brought the lawsuit.

“These are daunting and sometimes insurmountable hoops women are forced to jump through in time-sensitive circumstances, and we will continue our battle in court to remove these arbitrary restrictions on emergency contraception for all women," she added.

The application from Teva, based in North Wales, Pa., was pending before the judge's ruling, FDA officials said. Denise Bradley, a Teva spokeswoman, called the approval "a significant milestone for women."

Anti-abortion advocates objected to making emergency contraception more available to young girls because they believe that the emergency contraception drugs induce abortions.

Plan B One-Step is an emergency contraceptive aimed at reducing the possibility of pregnancy if taken within three days of unprotected intercourse. It uses a single pill that contains a high dose of the same hormone used in birth control pills to prevent or delay ovulation, prevent fertilization or, in some cases, prevent implantation of a fertilized egg in the uterine lining. Plan B One-Step will not end a pregnancy if a woman is already pregnant and there is no medical evidence it harms a developing fetus, FDA officials said.

Plan B, available from generic manufacturers, uses two doses of levonorgestrel. Another emergency contraceptive, ella, or ulipristal, is a prescription-only product that prevents pregnancy when taken within five days of unprotected intercourse. The FDA's decision Tuesday does not affect Plan B or ella.

Emergency contraception products do not protect against sexually transmitted diseases.